New York City's public transportation network is the most extensive in North America. About one in every three users of mass transit in the United States and two-thirds of the nation's rail riders are residents of New York City, or its suburbs. Data from the 2000 U.S. Census reveals that New York is the only locality in the United States where more than half of all households do not own a car (the figure is even higher in Manhattan, over 75 percent). While nearly 90 percent of Americans drive to their jobs, mass transit is the primary form of travel for New Yorkers.[1] New York's uniquely high rate of public transit makes it one of the most energy efficient cities in the country.

The Metropolitan Transportation Authority (MTA) operates most of New York City's transit systems. Using census data, the MTA reported in August 2006 that ridership on its buses, subways and commuter trains in recent years has grown faster than population growth, indicating that more New Yorkers are choosing to use mass transit, despite the poor service of some areas in New York City by mass transit.[2] The MTA attributed the ridership gains to the introduction of the MetroCard in 1993, and the replacement of more than 2,800 rolling stock since 2000.

From 1995 to 2005, the authority said, ridership on city buses and subways grew by 36%, compared with a population gain in the city of 7%. In the suburbs, it said, a 14% increase in ridership on Metro-North and the Long Island Rail Road outpaced a suburban population gain of 6%.[3] With dramatic increases in fuel prices in 2008, as well as increased tourism and residential growth, ridership on buses and subways grew 3.1% up to about 2.37 billion trips a year compared to 2007. This is the highest ridership since 1965.[4]

In 2013, ridership on the New York City Subway was 1.7 billion,[5] the highest ridership since 1946, despite Hurricane Sandy-related subway closures.[6] Ridership in city buses was 803 million.[5]

Over 5 million people ride the transit network each weekday, and the system is a major venue for commerce, entertainment and political activism. Much of the city relies on the subway as its main source of transportation and New York City is home to two of only five 24-hour subway systems in the United States. Campaigning at subway stations is a staple of New York elections akin to candidate appearances at small town diners during presidential campaigns in the rest of the country. Each week, more than 100 musicians and ensembles – ranging in genre from classical to Cajun, bluegrass, African, South American and jazz – give over 150 performances sanctioned by New York City Transit at 25 locations throughout the subway system, many under the Music Under New York program.[7] There are many more who are unauthorized performers, called buskers, ranging from professionals putting on an impromptu show to panhandlers seeking donations by way of a song.

One outcome of the city's extensive mass transit use is a robust local newspaper industry. The readership of many New York dailies consists in large part by transit riders who read during their commutes. The three-day transit strike in December 2005 briefly depressed circulation figures, underscoring the relationship between the city's commuting culture and newspaper readership.[8]

The subways of New York have been venues for beauty pageants and guerrilla theater. The MTA's annual Miss Subways contest ran from 1941 to 1976 and again in 2004 (under the revised name "Ms. Subways").

The subways and commuter rail systems also have some artworks in their stations, commissioned under the MTA Arts & Design umbrella.

The MTA-operated New York City subway and bus systems formerly used tokens or coins for fare collection. The use of tokens on these systems was discontinued in 2003.

The MetroCard is the current payment method for MTA-operated subway and bus systems, as well as for several other transporation systems in the metropolitan area. It is a thin, plastic card on which the customer electronically loads fares. Payment may be made at automated machines that accept money, credit cards, and debit cards. Variable pay schemes are available; cards with more pre-paid rides offer greater discounts. The MetroCard was introduced to enhance the technology of the transit system and eliminate the burden of carrying and collecting tokens.

In 2006, New York City's two main transportation systems, New York City Subway and PATH, announced plans to introduce smart cards for paying fares. In February 2006, the Port Authority of New York and New Jersey unveiled a $73 million smart card system in the World Trade Center PATH station. The PATH "SmartLink" card contains an antenna attached to a computer chip, which can be read by turnstiles without requiring passengers to swipe cards, similar to the TfLOyster card. The SmartLink card will eventually replace the magnetic-strip QuickCard accepted at PATH turnstiles. The MTA-owned subway and busnetworks will eventually use this same technology. A consortium of New York metropolitan transit agencies, including the Port Authority and New Jersey Transit, will test different versions and introduce a single standard. In the future, all New York City area transit systems will use the same "contactless" payment system, but this is not expected to be completed within the near future.

The Metropolitan Transportation Authority (MTA) is a New York State public benefit corporation tasked with providing mass transit in the New York City metropolitan area through its various subsidiary agencies.

MTA New York City Transit provides extensive fixed-fare subway and bus service (the latter controlled by Regional Bus below) throughout the five boroughs of New York City. The subway system is one of the largest in the world, with over 720 miles (1,160 km) of track and 468 stations. The free (except at St. George and Tompkinsville) Staten Island Railway, part of this system, provides north–south service along the entire length of Staten Island.

MTA Long Island Rail Road provides extensive commuter service to most of Long Island, with destinations in Kings, Queens, Nassau, and Suffolk Counties via two trunk lines and six subsidiary branches. The LIRR operates to and from a single station in Manhattan (New York County), Pennsylvania Station.

There are several proposals for expanding the New York City transit system that are in various stages of planning, initial funding, or completion:

In January 2007, the Port Authority approved plans for the $78.5 million purchase of a lease of Stewart Airport in Newburgh, New York as a 4th major airport for the area.[9]

World Trade Center Transportation Hub, whose construction began in late 2005, will replace the temporary PATH terminal that replaced the one destroyed in the September 11 attacks. This new central terminal, designed by Santiago Calatrava, will allow easy transfer between the PATH system, several subway lines and proposed new projects. It is expected to serve 250,000 travelers daily when it opens on December 15, 2015.

Fulton Center, a $1.4 billion project in Lower Manhattan that will improve access to and connections between 11 subway routes, PATH service and the World Trade Center site. Construction began in 2005, and it opened on November 10, 2014.

Second Avenue Subway, a new north-south line, first proposed in 1929, would run from 125th Street in Harlem to Hanover Square in lower Manhattan. The first phase, from 63rd Street to 96th Street, is under construction, and is scheduled to be opened to passenger service on December 30, 2016.

East Side Access project will route some Long Island Rail Road Trains to Grand Central Terminal instead of Penn Station. Since many, if not most, LIRR commuters work on the east side of Manhattan, many in walking distance of Grand Central, this project will save travel time and reduce congestion at Penn Station and on subway lines connecting it with the east side. It will also greatly expand the hourly capacity of the LIRR system. Completion is scheduled for 2023.

Gateway Project will add a second pair of railroad tracks under the Hudson River, connecting an expanded Penn Station to NJ Transit and Amtrak lines. This project is a successor to a similar one called Access to the Region's Core, which was canceled in October 2010 by New Jersey Governor Chris Christie, citing the possibility of cost overruns and the state's lack of funds. Amtrak is now in charge of the project, which is currently under construction and slated to be completed by 2020.[14]

Although New York City does not have light rail, a few proposals exist:

There are plans to convert 42nd Street into a light rail transit mall that would be closed to all vehicles except emergency vehicles.[15] The idea was previously planned in the early 1990s, and was approved by the City Council in 1994, but stalled due to lack of funds. It is opposed by the city government because it would compete with the 7 Subway Extension/IRT Flushing Line (7<7> trains).[16]

As part of a long-term plan to manage New York City's environmental sustainability, Mayor Michael Bloomberg released several proposals to increase mass transit usage and improve overall transportation infrastructure.[26] Apart from support of the above capital projects, these proposals include the implementation of bus rapid transit, the reopening of closed LIRR and Metro-North stations, new ferry routes, better access for cyclists, pedestrians and intermodal transfers, and a congestion pricing zone for Manhattan south of 86th Street.[27]

Note that this is a list of New York City Subway lines, which are the physical infrastructure over which services operate.
Lines with colors next to them are trunk lines; trunk lines determine the color of New York City Subway service bullets, except for shuttles, which are dark gray.